الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
The presented thesis is concerned with the densitometric, spectrophotometric and kinetic spectrophotometric analysis of certain cephalosporin antibiotics namely; cefaclor monohydrate, cefadroxil monohydrate, cefalexin anhydrous, cefradine anhydrous, cefotaxime sodium, ceftriaxone sodium, cefoperazone sodium, cefazolin sodium, cefixime, ceftazidime pentahydrate and cefpodoxime proxetil. It comprises three main parts in addition to general introduction about cephalosporin antibiotics and a literature review includes the official and reported methods for their determination.
Part 1:
Concerns with the densitometric methods for the determination of the studied cephalosporins and it consists of two chapters:
Chapter 1:
This chapter includes a simple, rapid, accurate, precise and selective densitometric method for the determination of four α-aminocephalosporins; namely cefaclor monohydrate, cefadroxil monohydrate, cefalexin anhydrous and cefradine anhydrous using nihydrin as a spraying reagent for detection and quantitation of the separated spots. Investigations were carried out to study all variables affecting the chromatographic conditions. Beer’s law was obeyed for all the studied α-aminocephalosporins in the concentration range of 2-10 µg/spot. The detection and quantitation limits for all the studied drugs ranged from 0.09 to 0.28 and from 0.27 to 0.84 µg/spot; respectively.
Chapter 2:
This chapter involves the development of a simple, rapid, accurate, precise and selective densitometric method for determination of seven cephalosporins; namely cefotaxime sodium, ceftriaxone sodium, cefoperazone sodium, cefazolin sodium, cefixime, ceftazidime pentahydrate and cefpodoxime proxetil using Dragendorff’s reagent for spraying, detection and quantitation of the separated spots. Investigations were carried out to study all variables affecting the chromatographic conditions. Beer’s law was obeyed for all the studied cephalosporins in the concentration range of 5-50 µg/spot. The detection and quantitation limits for all the studied drugs ranged from 0.35 to 2.48 and from 1.07 to 7.50 µg/spot, respectively.
Part 2:
In this part, the investigated cephalosporins were analyzed by a simple spectrophotometric method. This method depends on alkaline hydrolysis of all studied drugs and subsequent reaction of the formed sulphide ions with NBD-Cl in strong acidic medium to produce a yellow coloured chromophore measured at 390 nm. All variables affecting the reaction conditions were carefully studied. Beer’s law was obeyed for all studied cephalosporins in the concentration range of 5-160 µg mL-1. The detection and quantitation limits for all the studied drugs ranged from 0.29 to 5.87 and from 0.88 to 17.78 μg mL-1; respectively.
Part 3:
Includes kinetic spectrophotometric methods for determination of the investigated cephalosporins and it consists of two chapters:
Chapter 1:
This chapter comprises a kinetic spectrophotometric method for determination of cefaclor monohydrate, cefadroxil monohydrate, cefalexin anhydrous, cefradine anhydrous and cefixime. This method based on following the reaction rate by measuring the increase of the absorption intensity of iodine formed by a virtue of effect of the studied drugs acidity on a mixture of iodate and iodide. All variables affecting the reaction conditions were carefully studied. Beer’s law was obeyed for all studied cephalosporins in the concentration range of 5-50 µg mL-1. The detection limit and quantitation limit for all studied drugs ranged from 0.22 to 1.10 and from 0.67 to 3.33 µg mL-1; respectively.
Chapter 2:
This chapter describes a simple, rapid, accurate and precise kinetic spectrophotometric method for determination of three cephalosporins namely; cefoperazone sodium, cefazolin sodium and ceftriaxone sodium. This method is based on in-situ oxidation of quercetin into a red-coloured product measured at 510 nm. The reaction rate was followed by measuring the decrease in absorption intensity of oxidized quercetin caused by the reducing properties of the studied drugs. Investigations were carried out to study all variables affecting the reaction conditions. Beer’s law was obeyed for all studied cephalosporins in the concentration range of 40-400 µg mL-1. The detection limit and quantitation limit for all studied drugs ranged from 9.35 to 13.81 and from 28.34 to 41.86 µg mL-1; respectively.
A validation study for all the proposed methods according to ICH guidelines and USP 31 was performed. Moreover, all the proposed methods were successfully applied for the analysis of the investigated drugs in their pure forms and pharmaceutical dosage forms. Results were compared with those obtained from a previously reported method. The t- and F- values were calculated and compared with the theoretical values, indicating high accuracy and good precision for all the proposed procedures.
It might be noteworthy that the developed methods were subject matters of several research articles which were presented in national conference and published in international periodicals:
[1] S.R. El-Shaboury, G.A. Saleh, F.A. Mohamed, A.H. Rageh, ”Analysis of cephalosporin antibiotics”, J. Pharm. Biomed. Anal. 45 (2007) 1-19.
[2] G.A. Saleh, F.A. Mohamed, S.R. El-Shaboury, A.H. Rageh, ”Selective densitometric determination of four α-aminocephalosporins using ninhydrin reagent”, J. Chromatogr. Sci. (Accepted for publication, article in press).
[3] F.A. Mohamed, G.A. Saleh, S.R. El-Shaboury, A.H. Rageh, ”Selective densitometric analysis of cephalosporins using Dragendorff’s reagent”, Chromatographia (Accepted for publication, article in press).
[4] A.H. Rageh, S.R. El-Shaboury, G.A. Saleh, F.A. Mohamed, ”Spectophotometric method for determination of certain cephalosporins using 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl)” has been accepted for presentation as a poster at the Assiut University 6th International Pharmaceutical Science Conference, Faculty of Pharmacy, Assiut, Egypt, March 12-13, 2008, p. 92.
Also research article no. 3 has been accepted for publication as an oral research article at the same conference p. 135